Accession Number : ADA299920

Title :   Hierachical Modeling and Locking Effects in the Numerical Analysis of Multistructures.

Descriptive Note : Final rept. 1 Jan 92-30 Jun 95,

Corporate Author : MARYLAND UNIV BALTIMORE

Personal Author(s) : Suri, Manil ; Schwab, Christoph

PDF Url : ADA299920

Report Date : JUN 1995

Pagination or Media Count : 19

Abstract : The goals of this project were to (1) analyze numerical phenomena such as locking and boundary layers occurring in the modeling of elastic bodies, and obtain methods with robust performance, (2)extend this analysis to hierarchies of models, and (3) continue investigation into the p and h-p FEM. Specifically, the locking of hierarchy of plate models was analyzed to show that only the lowest order Reissner-Mindlin model effects were significant. Essentially locking-free h - mixed methods were established for the elasticity problem, Stokes flow, Reissner-Mindlin plate model and Naghdi shell. The h-p FE approximation of boundary layers was analyzed. Optimal convergence estimates for the 3-d version boundary element method were obtained. Numerical quadrature in the p version was analyzed and exponential convergence of an h - p quadrature scheme for singular integrals arising in boundary element and vortex methods was established. Wavelet based Galerkin boundary element methods as well as a convergent FEM for a class of nonconvex variational problems were developed.

Descriptors :   *ELASTIC PROPERTIES, *STRUCTURAL COMPONENTS, *LOCKING(MECHANICS), STRESS ANALYSIS, BOUNDARY LAYER, VORTICES, SHELLS(STRUCTURAL FORMS), PLATES, APPROXIMATION(MATHEMATICS).

Subject Categories : Structural Engineering and Building Technology

Distribution Statement : APPROVED FOR PUBLIC RELEASE